The head of the United Nations agency entrusted with curbing the spread of nuclear weapons said today he did not expect any “breakthrough” or “positive agreement” on Iran’s nuclear programme at the current meeting of the atomic watchdog’s Board of Governors now under way in Vienna.

“Unfortunately the picture is still hazy as to the scope and nature of Iran’s nuclear programme,” International Atomic Energy Agency (IAEA) Director-General Mohamed ElBaradei told reporters before formally presenting his latest report to the Board.

He said IAEA had not seen indications of diversion of nuclear material to nuclear weapons or other nuclear explosive devices during its inspections.

But he warned that there were still a number of “important uncertainties” that need to be clarified about the programme, which has been a matter of international concern ever since the discovery in 2003 that Iran had concealed its nuclear activities for 18 years in breach of its obligations under the Nuclear Non-Proliferation Treaty (NPT).

“I do not expect the Board to adopt a resolution on the Iranian issue unless there is a breakthrough and unless there is a positive agreement,” Mr. ElBaradei said. “As things stand I do not expect the Board to adopt a resolution.”

He added that as requested by the Board in February he would transmit his latest report to the Security Council, which has the power to impose economic sanctions. “There is universal recognition that this is an issue of serious implication to international peace and security,” he stressed. “The whole Middle East security is very much at stake.”

Iran says its activities are solely for peaceful energy purposes but the United States and other countries insist that it is clandestinely seeking to produce nuclear weapons. In August Iran rescinded its voluntary suspension of nuclear fuel conversion, which can produce the enriched uranium necessary either for nuclear power generation or for nuclear weapons.

As he has repeatedly over the past three years, Mr. ElBaradei called on Iran to provide “maximum transparency,” urging it to again freeze its research and development activities until a solution is found.

“Regrettably, however, after three years of intensive verification, there remain uncertainties with regard to both the scope and the nature of Iran’s nuclear programme,” he said in formally presenting the report to the Board.

“As I mentioned in my report, this is a matter of concern that continues to give rise to questions about the past and current direction of Iran’s nuclear programme. For confidence to be built in the peaceful nature of Iran’s programme, Iran should do its utmost to provide maximum transparency and build confidence.”

But he also warned against confrontation. “The only solution I see is a comprehensive agreement that covers the nuclear issue, the security issue, the economic issue and political issue,” he told reporters. “Confrontation could be counterproductive. It would not provide us with a durable solution.

“The earlier that we bring the parties back to the negotiating table the better for everybody. Meantime I call on all parties to exercise maximum restraint in their public statements.”